iPhone iOS 5.1

iPhone User Guide For iOS 5.1 Software

When you’re not using iPhone, you can lock it to turn off the display and save the battery.
Lock iPhone: Press the On/Off button.
When iPhone is locked, nothing happens if you touch the screen. iPhone can still receive calls, text messages, and other updates.

You can also:

Listen to music

Adjust the volume using the buttons on the side of iPhone (or on the iPhone earphones) while you’re on a phone call or listening to music

Use the center button on iPhone earphones to answer or end a call, or to control audio playback

Home button
The Home button lets you get back to the Home screen at any time. It also provides other convenient shortcuts.
Go to the Home screen: Press the Home button .